气相色谱法测定蔬菜中菊酯类农药

以等量混合的丙酮和石油醚为提取剂,石英毛细管色谱柱分离,电子捕获检测器检测的气相色谱法测定蔬菜中氯氰菊酯、氰戊菊酯、溴氰菊酯农药残留。以保留时间定性,外标法定量,3种菊酯农药的检测限分别为0.013mg/kg、0.010mg/kg、0.035mg/kg,相对标准差均<7%,加标回收率在75%～87%之间。该法较简便,满足了蔬菜食用安全性的鉴别要求。     

植物油脂废水处理工艺经济性分析

分析了植物油废水处理工艺，从工艺流程选择、预处理单元组合，絮凝剂优选、生物处理、污泥处理几方面讨论了提高植物油废水处理经济性的措施。     

蔬菜含锗（Ge）量的初探

研究发现，在普通蔬菜中亦不乏锗的存在。本文报导了１８个蔬菜品种可食部分的含锗量平均值为１．０３±０．４９ｍｇ／ｋｇ（以干物质计）。其含量因品种而异，也受土壤的影响。蔬菜含锗量相当于人参含锗量的４０％；蔬菜对土壤锗的富集系数在０．０５４０～１．１２之间；蔬菜中锗与其它１２种元素间无显著相关性。     

几种蔬菜汞富集能力的初步研究

对莴苣，木形、黄瓜，辣椒、豇豆，四季豆等６种夏季蔬菜汞吸收能力研究发现，在田间自然状上，６种蔬菜植株汞平均浓度为０．００３４７－０．００６３７ｍｇ／ｋｇ，其中总汞平均浓度最高，黄瓜最低；     

重庆市近郊蔬菜基地土壤和蔬菜中重金属的质量现状

通过对重庆市近郊蔬菜基地土壤和蔬菜中重金属的监测和评价得出：重庆市近郊蔬菜基地部分土壤受到 Ｃｄ和Ｈｇ的污染；部分蔬菜受到Ｐｂ和Ｃｄ的污染。     

砷对蔬菜生长的影响和临界值的研究

本文研究了紫色土添加砷对蔬菜生长的影响与临界值,并采用灰色系统的关联度分析方法,使它们与土壤性度联系起来,结果表明:三种紫色土砷的临界值一般为:红紫泥> 灰棕紫泥>红棕紫泥.     

太原市蔬菜中铅、铬和镉含量分析及安全性评价

笔者采用原子吸收光谱法 ,测定了太原市蔬菜批发市场的 8种蔬菜 72个样品的铅、铬、镉含量。结果表明 :在检测的 8种蔬菜中 ,有 5种蔬菜出现铅含量超标 ,铅是蔬菜中的主要污染元素 ,且污染带有普遍性 ;铬的污染仅出现在芹菜和青菜上 ,其他 6种蔬菜均无超标 ;8种蔬菜均未受到镉的污染 ,合格率为 10 0 %。参照国家食品卫生标准和蔬菜质量分级标准 ,对蔬菜的重金属污染程度进行了安全性评价。在所检测的蔬菜样品中 ,只有青菜受到重金属污染 ,其综合污染指数为 1.12 ,污染程度为轻度污染。其他蔬菜的综合污染指数均低于 0 .7,污染程度均为安全 ,污染水平均为清洁。     

哈尔滨市蔬菜生产基地土壤重金属污染状况评价

根据对哈尔滨市所辖8区蔬菜生产基地土壤环境的调查和监测,利用土壤综合污染指数进行评价,哈尔滨市蔬菜生产基地土壤质量状况。     

Reducing plant uptake of PAHs by cationic surfactant-enhanced soil retention

Reducing the transfer of contaminants from soils to plants is a promising approach to produce safe agricultural products grown on contaminated soils. In this study, 0-400 mg/kg cetyltrimethylammonium bromide (CTMAB) and dodecylpyridinium bromide (DDPB) were separately utilized to enhance the sorption of PAHs onto soils, thereby reducing the transfer of PAHs from soil to soil solution and subsequently to plants. Concentrations of phenanthrene and pyrene in vegetables grown in contaminated soils treated with the cationic surfactants were lower than those grown in the surfactant-free control. The maximum reductions of phenanthrene and pyrene were 66% and 51% for chrysanthemum (Chrysanthemum coronarium L.), 62% and 71% for cabbage (Brassica campestris L.), and 34% and 53% for lettuce (Lactuca sativa L.), respectively. Considering the impacts of cationic surfactants on plant growth and soil microbial activity, CTMAB was more appropriate to employ, and the most effective dose was 100-200 mg/kg.     

The concentrations, distribution and sources of PAHs in agricultural soils and vegetables from Shunde, Guangdong, China

The concentrations, distribution and sources of 16 polycyclic aromatic hydrocarbons (PAHs) were determined in 30 agricultural soil and 16 vegetable samples collected from subtropical Shunde area, an important manufacturing center in China. The total PAHs ranged from 33.7 to 350 μg/kg in soils, and 82 to 1,258 μg/kg in vegetables. The most abundant individual PAHs are phenanthrene, fluoranthene, chrysene, pyrene and benzo(b)fluoranthene for soil samples, and anthracene, naphthalene, phenanthrene, pyrene and chrysene for vegetable samples. Average vegetable–soil ratios of total PAHs were 2.20 for leafy vegetables and 1.27 for fruity vegetables. Total PAHs in vegetable samples are not significantly correlated to those in corresponding soil samples. Principal component analyses were conducted to distinguish samples on basis of their distribution in each town, soil type and vegetable specie. Relatively abundant soil PAHs were found in town Jun’an, Beijiao, Chencun, Lecong and Ronggui, while abundant vegetable PAHs were observed in town Jun’an, Lecong, Xingtan, Daliang and Chenchun. The highest level of total PAHs were found in vegetable soil, followed by pond sediment and “stacked soil” on pond banks. The PAHs contents in leafy vegetables are higher than those in fruity vegetables. Some PAH compound ratios suggest the PAHs derived from incomplete combustion of petroleum, coal and refuse from power generation and ceramic manufacturing, and paint spraying on furniture, as well as sewage irrigation from textile industries. Soil PAHs contents have significant logarithmic correlation with total organic carbon, which demonstrates the importance of soil organic matter as sorbent to prevent losses of PAHs.